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flatheadmurre · 12-12-2018, 03:26 AM

You can use a resistor in series wth the solenoid but you need to change the relay to 12v.
If you put the resistor in the feed to the circuit the relay will see 12v everytime it´s activated since resistor won´t drop enough voltage until the solenoid is activated.
Why doesnt the resistor drop the voltage for the relay then ??...it´s all about ohms law...the coil of the relay takes less then an amp in current draw so until the solenoids load is added to the circuit the resistor drops less then a volt.
Switched power supplies DC-DC converters are dirtcheap today...but you need to know what current it will take....and you need to ad an external capacitor to deal with peak current draw of the coil...besides that a resistor is way more bullet proof...

12-12-2018, 03:26 AM	#4
flatheadmurre Senior Member Join Date: Apr 2015 Location: Sweden Posts: 3,045	Re: 12 volt conversation 6 volt overdrive You can use a resistor in series wth the solenoid but you need to change the relay to 12v. If you put the resistor in the feed to the circuit the relay will see 12v everytime it´s activated since resistor won´t drop enough voltage until the solenoid is activated. Why doesnt the resistor drop the voltage for the relay then ??...it´s all about ohms law...the coil of the relay takes less then an amp in current draw so until the solenoids load is added to the circuit the resistor drops less then a volt. Switched power supplies DC-DC converters are dirtcheap today...but you need to know what current it will take....and you need to ad an external capacitor to deal with peak current draw of the coil...besides that a resistor is way more bullet proof...